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Might have / Must have

Making guesses and drawing conclusions

sad
 

 

What Happened?

MIGHT  HAVE

Might expresses an opinion: an uncertain guess, a speculation, based on very little information. Might have expresses an opinion about an earlier (past) situation.

A GUESS

The car driver might have tried to pass between two buses.

One of the bus drivers might have changed lanes without looking first.

The bus drivers might not have been able to see the smaller, lower car.

The road might have narrowed and so they all tried to move into the same lane.

MUST HAVE

Must expresses an opinion: an inference, a conclusion, based on known details. Must have expresses an opinion about an earlier (past) situation.

A CONCLUSION

The car driver must have panicked when he saw the buses moving in on both sides.

The bus passengers must have heard a crunch. (sound)

The car passengers must have escaped out the back.  (No other exits were available.)

The insurance company must have declared this car "totaled".

 

infer (v.) – to form an opinion that something is probably true because of information that you have
inference (n.) – an opinion that is formed on details or knowledge that you have
panic / panicked (v.) – a sudden strong feeling of fear or nervousness that makes you unable to think clearly or behave sensibly
speculate (v.) – to guess about the possible causes or effects of something, without knowing all the facts or details
totaled (adj) – not worth fixing; totally gone

See Modal Review  "Degree of Certainty / Possibility"

 

 

 

 

 

 

Must

Two Meanings (commonly confused)

 

 

 

Conclusion vs. Necessity

MUST – CONCLUSION

Must have expresses an inference (conclusion) based on known details.

Traffic officers must be accustomed to seeing occasional bizarre accidents like this one, because they see so many accidents each year

The passengers in the car must have been extremely frightened.

MUST – NECESSITY

Must can be used when stating opinion about what needs to be done.

Drivers must not make unsafe lane changes. (present tense)

Each of the drivers had to file an accident report. (present tense)
 

 

 

 

 

 

 

 

Sentence Types

Word Order

 

 

 

SENT TYPE SUBJECT MODAL VERB BASE  
STATEMENT        

guess

She

might

be

upset. 

inference

She

must

be

upset. 

NEGATIVE        

guess

She

might not

be

upset. 

inference

She

must not

be

upset. 

PAST        

guess

She

might have

been

upset. 

inference

She

must have 

been

upset. 

NEG. PAST        

guess

She

might not have

been

upset. 

inference

She

may not have

been

upset. 

W / ADVERB        

guess

She

might really have

been

upset. 

inference

She

must truly have

been

upset. 

 

 

 

 

 

 

Practice

Plane Sight

A pun on "in plain sight"

plane on highway

 

 

What happened?

  1. Select the response from the list that best completes the sentence and fits the situation pictured above. 
  2. Compare your response to the feedback by clicking the "check 1-10" button at the bottom or the "check" button to the left of each item.

 

1.

2.

3.

4.

5.

6.

7.

8.

9.


10.

 

 

 

 

 

 

 

Practice 2

Sink Hole

Car sinking
 

 

Read for Errors

Diana: It looks as if the ground is swallowing the car. Rain must of washed the soil away under the road.

Alan: Or a water main might have broke leaving a hole.

Diana: I wonder how the car got there. The driver might parked it there the night before.

Alan:: Or the driver might have trying to pass the damaged road by driving on the side.

Diana: Either way, the driver must being frustrated to learn his car is caught in the hole.

soil (n.) – dirt, earth

swallow (v.) – consume, eat

water main (n.) – water supply pipe

 

 

 

Correct or Incorrect?

  1. Select the correct or incorrect option to describe the text in bold italics.
  2. Compare your response to the feedback by clicking the "check all" button at the bottom or the "check" button to the left of each item.

 

11.
Diana: It looks as if the ground is swallowing the car. Rain must of washed the soil away under the road..

   

12.
Alan: Or a water main might have broke leaving a hole..

   

13.
Diana: I wonder how the car got there. The driver might parked it there the night before.

   

14.
Alan: Or the driver might have trying to pass the damaged road by driving on the side. 

   

15.
Diana: Either way, the driver must being frustrated to learn his car is caught in the hole.

   

 

 

 

 

 

 

 

Practice 3

Mystery of Hudson Bay Killer Whales

trapped whales
 

 

Read  the Context

A pod of killer whales was found surfacing through a breathing hole in the ice of Hudson Bay, Quebec.  The whales were taking turns rising up through a single hole which was about the size of a pickup truck. The whales (became) trapped by a late winter freeze.  Observers thought there (were) as many as a dozen whales including several small ones.  Some observers worried that some whales (become) trapped under the ice and died.  The mayor of the remote Inuit community called for an icebreaker to save the whales, but none was nearby. Other people made plans to enlarge the 30 by 30 foot ice hole with chainsaws. The mayor was against these plans because they (put) local people in danger of falling into the ice hole.  However, changing weather conditions overnight allowed the ice to break up and the whales to escape.

 This incident was rare. Normally, as the ice moves in and breathing holes close up, Arctic animals move south. This pod of whales (was) confused.  Biologists believed that the late freeze (caught) the whales unexpectedly.  With global warming the Arctic area is freezing over later and later.

The area usually freezes over at the end of November. Locals think these whales (stayed) to feed on an abundant supply of seals, sea lions and other small whales.

The local people found that neither they nor the Canadian government was well-equipped to help the whales escape. Had the ice not broken on its own, most of the whales would have died.  For the remote Inuit community of Inukjuak, Quebec, this (was) a worrisome experience.  Fortunately for all, it turned out well. 

"The Mystery of Hudson Bay's Trapped Killer Whales." The Pew Charitable Trusts. N.p., n.d. Web. 02 Jan. 2014. <www.pewenvironment.org>.   

oldenberg, Suzanne. "Stranded Killer Whales Break Free from Hudson Bay Ice." Theguardian.com. Guardian News and Media, 11 Jan. 2013. Web. 02 Jan. 2014. <guardian.co.uk/environment/2013/jan/10>.   

abundant (adj.) – exists in large quantities; more than enough

breathe (v.) – take air into the lungs and let it out; respire

chainsaw (n.) – small equipment that cuts wood or ice

escape (v.) – get away or out of a small space (jail, prison)

freeze (v.) – become cold and change from water to ice

icebreaker (n.) – a large ship capable of breaking through ice

incident (n.) – situation, circumstance; event

Inuit – people of the Arctic; Alaska, Greenland, Canada

locals (n.) – local people; people who live nearby

panic / panicked (v.) – a sudden strong feeling of fear or nervousness that makes you unable to think clearly or behave sensibly

observer (n.) – a person who is watching, paying attention

pod – quantifier for a family of whales or dolphins

remote (adj.) – far away from city centers; distant

surface (v.) – rise above water  into the air

supply (n.) – an amount of something that you are able to use

take turns – one after the other; share in a fair manner

trapped (adj.) – caught within a small space or object

 

 

 

 

Change the wording to a past modal — might have or must have.

  1. Edit the sentence to include a modal: might have or must have.
  2. Compare your response to the feedback by clicking the check button.

 

16.
Local people speculated: the whales became trapped by a late winter freeze.


17.
Observers guessed: there were as many as a dozen whales including several small ones.


18.
Some observers worried that some whales became trapped under the ice and died.


19.
The mayor was against these plans because they (put) local people in danger of falling into the ice hole.


20.
Biologists inferred: This pod of whales was confused.


21.
Biologists believed that the late freeze (caught) the whales unexpectedly. 


22.
Locals think these whales stayed to feed on an abundant supply of seals, sea lions and other small whales.


23.
For the remote Inuit community of Inukjuak, Quebec, this (was) a worrisome experience.